Excavating machine



Nov. 1, 1955 s. R. DEMPSTER EXCAVATING MACHINE Original Filed Aug. 31, 1951 2 Sheets-Sheet l INVENTOR 5207376 12 pem asfr MB Q Nov. l-, 1955 G. R. DEMPSTER EXCAVATING MACHINE 2 Sheets-Sheet 2 Original Filed Aug. 31 1951 INVENTOR flempszr ATTORNEYS United States Patent Office 2,722,325 Patented Nov. 1, 1 955 EXCAVATING MACHINE George R. Dempster, Knoxville, Tenn.

Original application August 31, 1951, Serial No. 244,650. Divided and this application October 3, 1952, Serial No. 312,944

2 Claims. (Cl. 214-142) This application is a division of my prior application Serial No. 244,650, filed August 31, 1951, now abandoned.

This invention relates to improvements in excavating machines, and more particularly to such excavating machinery as is known as power shovels, loading machines and the like, adapted for digging or lifting either loose material or articles that are adapted to be raised to an elevation and dumped.

This invention is an improvement on the loader of the dipper type, set forth in my prior application, Serial No. 747,689, filed May 13, 1947, now Patent No. 2,600,739, dated June 17, 1952.

The object of the invention is to improve the crowding action of the excavating machine by providing a yielding action on the bucket during the crowding action of the excavating machine which will aid in directing the bucket intothe material.

This object can be accomplished by the provision of a resilient bumper in such position on the excavating machine that it will apply a bumping action directly to the door of the bucket at a point which will yieldably impart movement to the latter into the material and thereby enhance the crowding action of the machine, which bumper mounted directly on the frame of the machine may be used for this purpose for direct abutment by the bucket.

One embodiment of the invention is illustrated in the accompanying drawings, in which:

Fig. 1 is a side elevation of an excavating machine to which this invention is applied;

Fig. 2 is a plan view partly in section showing the bumper structure for the bucket; and

Fig. 3 is a perspective view partly in section of the bucket and tripping mechanism therefor.

The excavating machine shown as an embodiment of this invention comprises a power driven vehicle having a frame structure generally indicated by the numeral I mounted on wheels 2 and self-propelled by a power plant generally indicated at 3. The details of the self-propelled vehicle are not illustrated and described because these have been set forth more in detail in my prior application, Serial No. 747,689, filed May 13, 1947, and may be varied as desired.

A steering wheel is designated generally by the numeral 4 adapted to be controlled by an operator on a seat 5 intermediate the length of the machine. Suitable control levers are designated at 6 for a purpose hereinafter described, two of which may be provided in side-by-side relation. Other controls are omitted from the illustration, but it will be understood that the required controls are used. A lever 7 is a gear shift lever to control the speed of movement of the vehicle in a manner well understood in the art of automotive vehicles.

' Extending upwardly from the frame 1 adjacent one end portion thereof is a support 8 preferably one on each side of the vehicle. The support 8 has mounted thereon oneend of a boom 9 pivoted to the support v8 at 10. It is preferred that a separate boom member be provided The boom 9 is adapted to be raised and lowered by-a' pair of hydraulic power devices generally indicated at 12 pivotally supported at their lower ends at 13 on the frame 1, and pivotally connected at 14 at their upper ends with a bracket 15 on each boom member. Any suitable form of power device may be used as desired, that illustrated having a hydraulic cylinder with a piston mounted therein under the control of the operator upon manipulation of a valve by one of the control levers 6.

At the free end of the boom 9 is suspended a lifting bar or link 16, preferably comprising two link members and pivoted to the free end of the boom 9 at 17. The lower ends of the members 16 are pivotally connected at 18 with a dipper, such as a bucket or other receptacle, generally designated at 19.

material, dirt, rock, etc. A door 20 normally closes one side of the bucket 19 and is adapted to be opened when the bucket is raised for discharging the contents therefrom, in which position the bucket is turned substantially to an upright position as hereinafter described more in detail.

The door 20 is supported on a pair of arms 21, 'the upper end of each of which is turned over in the form of a gooseneck and is pivotally connected at 22 on a bolt or suitable fastening pin to the side of the bucket 19, as shown particularly in Fig. 3.

A crowd unit is provided on the vehicle for manipulating the bucket 19 which crowd unit comprises an upright crowd member 23 pivotally supported at 24 on one end of the frame 1, having a crowd link 25 pivotally connected at 26 with the upper end of the crowd member 23. The crowd link 25 extends downward to the adjacent side of the bucket 19 to which it is pivotally connected by the pin 18. This crowd link 25 also has an offset arm 27 which extends laterally therefrom and is connected by the pivot pin 22, thereby forming a connection between the bucket 19 and the crowd link 25 which will insure the movement of the bucket bodily upon swinging movement of the crowd link 25. Like the boom 9, it is preferred to use a pair of members spaced laterally of the frame 1, for the crowd unit.

The crowd-unit 2325 is adapted to be manipulated by power devices generally indicated at 28, each of which preferably is a hydraulic power device comprising a cylinder and piston. One end of each power device is pivotally connected at 29 with the upright crowd member 23 while the opposite end is pivotally connected'at 30 with the frame 1. These power devices 28 for the crowd unit may be controlled by a valve adjusted by the other control lever 6.

The foregoing excavating structure is substantially in the form set forth and claimed in my prior application, Serial No. 747,689, filed May 13, 1947.

In the form here illustrated the door 20 of the bucket 19 is adapted to be fastened in closed position by latch mechanism of the character shown in Fig. 3. This latch mechanism comprises a slide bolt 31 mounted on the door 20 in position for engaging a keeper 32on a side of the bucket 19, and when engaged with said keeper to hold the door 20 latched in closed position. The bolt 31 is connected loosely with a lever 33 pivoted at 34 to the door 20 and normally held in its lower position by the spring 34'.

pull bar 36 has a screw threaded connection 37 with the socket for an adjustment lengthwise relative thereto so as to obtain the proper degree of movement of the latch under different conditions.

The free end of the pull bar 36 is provided with a link 33 to. which one end of a chain 39 is connected. Any other suitable form of flexible connection may be substituted for the chain 39 to provide for freedom of movement of the latch lever 33 upon the application of a pull thereto. This chain 39 is shown as provided with an adjusting link 40 intermediate the length thereof to vary the length of the chain to take up the slack. In the form illustrated, this adjusting link is in the form of a bolt extending through adjacent links of the chain and connecting the latter together.

The opposite end of the chain 39 is provided with a swivel link 41 connected by a collar with a crank pin 42, eccentrically mounted on a gear 43. Any suitable form of crank action means may be substituted for the gear 43 and its crank pin 42.

The gear 43 is journaled on a pin 44 mounted in a suitable'bearing on a support bar 45 which extends between spaced crowd link members 25 and is carried by the latter. This bar may be secured by welding or other suitable manner to the members 25.

Also mounted on the bar 45 is an electric motor 46 having a pinion 47 on the armature shaft thereof meshing with the teeth of the gear 43 forming a drive connection with the latter upon energizing of the motor. One example of the driving connection may use a l5-tooth pinion 47 meshing with a 96-tooth gear 43 so as to provide the desired speed reduction of about 6 to 1 in the operation of the latter, although the speed thereof may be varied as desired.

A cover is shown at 48 for enclosing the motor 46, fitting over the latter, with opposite ends open or partially closed, as desired. It is bolted or otherwise fastened securely but detachably on the mounting bar 45 to enclose the motor to the desired extent and yet provide for access thereto when needed.

An electric cable is shown at 49 connected at one end with the motor 46 and extending therefrom along the crowd unit 23-25 and the frame of the machine to a suitable push button switch 50. The latter preferably is mounted on the control lever 6 that controls the crowd unit so as to be manipulated by the thumb of the operator when the bucket 19 reaches the desired point for dumping, thus making it unnecessary for him to remove his hand from the crowd controlling lever for dumping the bucket. A suitable source of electric current, such as a battery, is connected with the switch 50 so as to energize the motor 46 upon closing the switch. The circuit to the motor may be the usual single wire circuit where one side of the motor is grounded to the frame of the vehicle or it may be a two wire circuit in which the current travels through the cable to and from the source of; the electric current as desired.

It will be apparent that the excavating mechanism will be operated substantially as described in my prior application, Serial No. 747,689, filed May 13, 1947, wherein the operator manipulates the vehicle for travel in a direction toward the right in Fig. 1 into the material to be excavated with the bucket in the lower position as shown. The bucket may be forced into the material by the traction of the vehicle. This scooping action can be increased by manipulation of the crowd unit 232 5 alone or with the upward swinging movement of the boom 9 with operation of one or both of the power devices 28 and 12 respectively.

As soon as the bucket has been filled and movedto its elevated position, usually upright with the door 20 at the bottom of the bucket, the latter may be released for dumping the contents. It is also possible with this in: vention to dump the bucket at any point desired without the necessity for raising it to its top position. This is ac-.

mp is s y, m n p a n of. he. t h 50, to energize.

the motor 46 and thereby rotate the gear 43. Only a momentary energizing of the motor is required, although longer operation thereof does no harm, since it is sufficient to move the gear 43 through one revolution. However, sometimes the door sticks and is not readily opened, especially with wet or sticky material, and in that event, an additional length of time for operation of the gear 43 aids in releasing the door. This turning movement of the gear 43 imparts a pulling action to the chain or flexible device 39, thereby raising the free end of the latch lever 43 and withdrawing the bolt 31 from the keeper 32. The door is thus released from its closed position for dumping the contents.

The direct connection of the motor driven gear or other eccentric device with the latch lever insures a positive operation of the latch with very simple mechanism without the danger of interfering with the operation of the crowd unit or the bucket. At the same time the opening action of the door is facilitated against sticking in closed position by the latch release means shown and described. After dumping of the contents of the bucket 19 the latter is lowered again to its excavating position and the door 20 closes automatically by gravity.

As the bucket reaches its lowered position the hinge bars 21 engage at the edges thereof against a bumper plate 51 mounted at the end of the frame 1. As shown in Fig. 2, the bumper plate 51 has pins 52 attached thereto extending through compression springs 53 telescoped into cups 54, being interposed between the closed ends of the latter and the bumper plate 51. The tension on the compression springs 53 may be adjusted by the screw threaded connection of the nuts 55 with the pins 52. The cups 54 are welded or otherwise secured to a connecting member 56 extending between the free ends of a sub-frame 57 that is attached to the frame 1 and held in secure relation thereto.

This yieldable bumper bearing against the bucket 19 not only cushions the backward swinging movement of the bumper but also imparts resiliency to the latter as it is forced into the material. Furthermore, the springs 53 aid in the crowding action of the unit.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein without departing from the invention as defined in the claims.

I claim:

1. In an excavating machine, the combination of a mobile frame, a dipper having a dumping door, support ing arms carrying the door and pivotally mounted on the dipper, a crowd unit operatively connected with the frame for supporting the dipper thereon for bodily movement relative to the frame, power means for operating the crowd unit, a n d' a resilient bumper mounted on the frame in position to be engaged by the arms of the door upon movement of the dipper to an excavating position, said bumper including a bumper plate in position to be engaged by the arms, guide pins connected with the plate,

a sub-frame connected with the mobile frame, tubing members mounted on the sub-frame, and compression springs extending into the tubing members and interposed between the latter and the bumper plate and surrounding the pins for applying yielding pressure to the plate, said guide pins extending through the tubing members and compression springs and having means thereon for com fining the compression springs between the tubing members and the bumper plate.

2. In an excavating machine, the combination of' a mobile frame, adipper having a dumping door, supporting arms carrying the door and pivotally mounted on the dipper, a crowd unit operatively connected with the frame for supporting the dipper thereon for bodily movement relative to the frame, power means for operating the crowd unit, a resilient bumper mounted on the frame and extending ttat sy t sly. hereof. hr gh t. the. id h of the dipper and in position to be engaged by thearms of the door upon movement of the dipper to an excavating position, said bumper including a bumper plate in position to be engaged by the arms, and compression springs acting on the bumper plate for applying yield- 5 ing pressure thereto and yielding under action of the dipper.

References Cited in the file of this patent UNITED STATES PATENTS Greenleaf Apr. 10, 1923 Biedess Apr. 22,1941 Shinn, Jr. Jan. 4, 1944 Biedess Jan. 22, 1952 Dempster June 17, 1952 Brett Jan. 20, 1953 

